RavenDB - Computed Properties - ravendb

Question

I have a document with a few computed properties. Properties that have no setter and can call other methods on my class to return a result, example:
public class Order
{
public string CustomerId { get; set; }
public string VehicleId { get; set; }
public DateTime OrderDate { get; set; }
public decimal CommissionPercent { get; set; }
public List<OrdersLines> OrderLines { get; set; }
public decimal Total
{
get { return GetOrderLinesTotal() + SomeDecimal + AnotherDecimal; }
}
public decimal GetOrderLinesTotal()
{
return OrderLines.Sum(x => x.Amount);
}
}
I use a simple index to search for Orders by customer, date and some properties on the Vehicle document using lucene query and a Transformer to create my view models. I've looked at Scripted Index Results and I'm not sure if it would apply in this case.
public class ViewModel
{
public string OrderId { get; set; }
public string CustomerName { get; set; }
public string VehicleName { get; set; }
public string Total { get; set; }
}
How do i get the computed value from the Total property when I query these documents?
I've simplified the GetOrderLinesTotal some what, in fact it is a complex method that takes a lot of other properties into account when calculating the total.
I only get the computed value that serialized when the document was created or updated.

Answer 1

I realized that this is more a of a document design problem rather than trying to do something RavenDB was not meant to do. I simplified my document and used a map/reduce to solve the problem.

Answer 2

I think your situation is similar to a problem I once encountered. I use a JsonIgnore attribute on my public get property and use a private backing field, which I include in serialisation using the JsonProperty attribute. You should be able to apply a similar idea hopefully:
/// <summary>
/// The <see cref="Team" /> class.
/// </summary>
public class Team
{
/// <summary>
/// The ids of the users in the team.
/// </summary>
[JsonProperty(PropertyName = "UserIds")]
private ICollection<string> userIds;
// ...[snip]...
/// <summary>
/// Gets the ids of the users in the team.
/// </summary>
/// <value>
/// The ids of the users in the team.
/// </value>
[JsonIgnore]
public IEnumerable<string> UserIds
{
get { return this.userIds; }
}
// ...[snip]...
}